Catalytic conversion of propene into higher boiling hydrocarbons



T y, puma; deanedve ege er "'QPerhaps the most com m ny mi i United States Patent Ofi 3,161,697 Patented Dec. 15, 1964 3,161,697 CATALYTIC CONVERSION OF PROPENE INTO HIGHER BOILING HYDROCARBONS Johannes H. Choufoer, Hendrikus dc Ruiter, and Dick van Zoonen, all of Amsterdam, Netherlands, assignors to Shell Oil Company, New York, N.Y., a corporation of Delaware No Drawing. Filed Oct. 31, 1960, Ser. No. 65,896 Claims priority, application lfetherlands, Apr. 29, 1960,

251, 02 s l 6 Claims. (Cl. 260-68315) This invention relates to a process for the catalytic conversion of propene into higher boiling hydrocarbons. More particularly, the process relates to thccatalytic conversion of propene intohigher branched chain ,r 1? im The conversion of normally gaseous hydrocarbons, such as propene, into high octane-gasoline components by means of catalytic processes such as polymerization and alkylation is well known. Catalysts for tion of olefins are primarily acidic nature, the most commonly used catalysts being sulfuric acid and phosphon'c acid. Other catalysts, such as aluminum chlorid zinc chlcride, titanium chloridq and activated enys are known. Synthetic 'silica almnin'a isolso occasione,

' arly-e relatively smallpercentage oiolefins v erizing propene imeai fi r; polymerizationover a solid phoric acid supported on fieselguhr. In this'pnocess the" p p is to b fi e a dime f trimer and tetramerwhich an: valuable of their" high octane rating. -Howeve'r; their prcsencejn motor gasoline in recent years been y,;

able because of their I pollution problems. BY .difierenoe in octane rating determined by 1 1 and the octane tiithe g olefinic pfoducts can be converted to'thelcones pending Hydrocarbon .by separatehydrogenation process, usually bye catalytic employing,

such catalysts as .mngstenfmolybdimm, mangancsq iron, 1

nickel. cobalt, etc, their sulfides and aides and combinations thereof. hydrogenation. istachieved in; separate process which oierafing costs v Y is w: .11

In the elkylation'process, propene is converted into higher boiling hydrocarbons by alkylating' it with isobutane in the presence ofa'mineral acid catalystisuch as concentrated sulfuric acid. The alkylate, parafiinic hydrocarbons which have a high octanerafing, is-a valuable componefi inghsoline blending. However, the alkylation process requires isohutane which is usually limited supply and also is an expensive process. 1

It has now been found that prop-Que can be convert in high yields to higher boiling branched hydrocarbons by contacting the propene with a solid catalyst comprising an acidic component and a hydrogenation component. The conversion is carried out at an elevated temperature and pressure in the presence of hydrogen or a hydrogeucontaining gas.

The catalyst used in the process of the invention comprises a sulfide of one or more of the metals of the left-hand column of Group Vl (chromium, molybdenum, tungsten) and/or a sulfide of one or more of the metals of Group VIII (iron, cobalt, nickel) of the Periodic Table 5 deposited on a solid acidic support which in itself has catalytic properties. By a solid acidic support it is meant those which, when absorbing butter yellow and still other weaker basic indicators, show a color change of these indicators, indicating the transition to the acid form. Suitable acidic supports for the dual-fimction catalysts of the invention are compounds of silica and alumina, such as silica-alumina ciackingcatalyst, compounds of silica and zirconium dioxide, compounds of boron trionide and alumina, compounds of boron trioxide and silica compounds, compounds of alumina and halogens such as;alumina and fluorine, and the like. A supof silica-alumina compounds, and particularly those'havinga silica content of at least 60% by weight and an alumina content of about 140% by .We s ja s m q a v A component having hydrogenation activity is deposited or distended on the solid acid catalyst component. Suitable, com nents showing hydrogenation activity are sulfides of the metals-ofethe left-hand column of Gioup i d/ t t e metals pffllroup vfll of the Periodic I QIabIe NickelfisuIfide audios-cobalt sulfide areparticwide limitsandisgenerally in t eme it-1 m M05 to about= 5.% y igh E t t h for p e a c ys n a n s s i nl m na ,and e a silica ntent pint leade gooflh' by yveight (based on the total catalyst) and to which is applied 1 to 10%,;byweight pf nickel as sulfide, (based Lonf the .t otal; catalyst) an excellent catalyst for use in the process of the invention. -The arietal-sulfide applied to the acid catalystsuppcrt, I ,lforjnstance silica-alumina cracking catalyst, byany suitable method knowneper-ser For example, the metal ppfic bvi n s e the add-catalyst ii-solution oi'a salt of the corresponding metal, for nitr aoe, followed by drying, calcining and y s e i hhy w n sulfide or a s c i v 1. The silicaealumina support preferably is calcined at an elevated temperature prior to impregnation with the e temperaturesup toabout 6Q)? C. Higher calcination generally are undesirable since they lead 1e increased ,dispmportionation reactions in the conver- Intlmpmcessoitheinvention, propeneismainly corivetted into higher boiling branched paraflins and/or branched olefins with branched hydrocarbons having 4, 5 and 6 carbons atoms per molecule being formed predominantly. Little or no hydrocarbons boiling lower than propene are formed in Iheprocess. The hydrocarhon feed to th e process can be substantially pure propene or a. mixture of hydrocarbons containing, in addition to propene, fairly large quantities of other compounds such as propane. For example, an excellent feed for the process of the invention is a C traction recovered from a thermal or catalytic cracking process. Other olcfins, particularly higher boiling olcfins, can be present in the hydrocarbon feed and are mahlly converted into branched metal sulfide, calcination can be carried out at e '2 O or more highly branched parafiins and/or olefins. The isomerization of normal butene and higher normal olefins over catalysts comprising nickel sulfide on cracking catalysts is described in copending application Serial No. 39,818 filed June 30, 1960 by Ioost C. Platteeuw and Johannes H. Choufoer.

The exact manner in which the conversion reaction proceeds is not known but it is considered to be a complex mechanism involving polymerization, cracking,

isomerization and hydrogenation reactions.

The degree of saturation of the final product depends on the composition of the catalyst and the reaction conditions used, since the catalyst has the property of wholly or partly converting into saturated hydrocarbons both the olefins present in the starting material and the olefins (mainly branched) vformed during the reaction of the propene. In this connection, the reaction conditions, in particular the liquid hourly space velocity, are important. A lower liquid hourly space velocity results in a more drastic hydrogenation of'the unconverted Olefins aswell as any'olefins formed. Liquid hourly space velocity of the starting materials to be converted generally varies from 0.5 to 20 liters of liquid hydrocarbons per hour per liter of catalyst (11111.), although lower or "cbnditions'are such that there is little or no hydrogenation of the reaction product, the product may, if desired, be separately e'atalytically hydrogenated in the usual manner Y known persegfor instanoe by means of a catalyst con taining nickel, platinum, or cobalt oxide, molybdenum oxide.

The propene conversion is carried out in the presence or 'or'a hydrogen-containing gas at an elevated preferably a'ta within the range of oommate 100 ind particularlyat a total in the range ofirom 20 1660 atmospheres 'iotal pressures exceeding 100 atmospheres preferably arefnot used, higher the-presure thelower is the yield of The hydrogen pressure can vary" "-wrthm" I wide and-is pref erably from-50% tic-' 95% of-the -"Pui'e hydrogmned 110mm {eerily be used as hydrogen containingim' such as hy- W a w i we e r m 500 fiend-preferably at about 200 C. to 400 C. The in have excellent activity even'at theprefcnedlowtemperatnres. 1 'Iheproce'sottheinvention can be med also'with para'dvania g wh'enihe olefinic starting material containi: such for example, propadiene and 'inc'thylaetylen'e. life of'solid catalysts used alone heretofore was foundto be very short, particularly with such "stocks containing diolefins, and this is presumably due -to the formation of diene polymers and the like which deposit onsth'e'catalyst and rapidly reduce activity. In the present process, however, the dienes selectively hydrogenated to the monoolefins which in-the conversion reaction (or anysub- .seqnent hydrogenation reaction). This not only extends the life of the catalyst, but leads to .a higher yield of branched hydrocarbons.

The following examples er illustrate the principles of the invention and iho'w -iir'more detail one method of carrying it out. They also indicate the advantages, par: ticularly with respect to conversion of propene to higher boiling branched chain hydrocarbons:

EXAMPLEI A mixture of propane and hydrogen (molar hydrogen/ hydrocarbon ratio=4:1) was passed over a solid acidic catalyst consisting of 83.8% by weight of silica, 11.4% by weight of alumina and 4.8% by weight of nickel sul- :1 fide at a total pressure of 20 l:g./sq.cm., a temperature of 300 C. and a liquid hourly space velocity of 2 l/h.l.

The following table shows the composition of the reaction product after a test period of 5 hours.

The data in Table I show that only very slight quan tities of methane and C -hydrocarbons are formed, whereas high yields of branched Cg, C and c -hydrocarbons velocifiw y used lfp h fi 25 are It is noticeable 3150 that hydrocarbons having a higher boiling point than propane and propene are almost entirely absent. I

EXAMPLE II V A silica-zirconia cracking catalyst 9S of silica to 5 parts zirconia by weight isimpregnated with cobalt nitrate. After drying for two hours at 180' C. and calcining in air for two hours at 500 C., the catalyst is prepared for use in the of theinventionfby passing hydrogen sulfide over it for abodt 4 hours at 500 C. A C; cracked fraction proximately 60% propene and 40% V V with hydrogen (hydrogen/propelle mom-mac new proximately 6:1),over thecatalystata'totalpressxireotflfl atmospheres, a temperatnre'of 215 C. and ajliquid eed velocity of 2.5 l/hl. The propene is higher boiling branched hydrocarbonswith no formation of hydrocarbo mil y, i g 6f frmloo, c. to 'Asolunon'of'966gofAlCl,.6aq.mlolitersofwater was mixed intensivelywith' 10 liters of ammonia fromftionof2.7% concentration. lldixingtookplacebytangentially introducing each solution at a rate of 20 liters'per hour mm a mixing chamber, in such awaythat mixing the pH was between 8 and 8.5. Precipitation of the aluminum hydroxide gel was carried out without heating.

As soon as precipitation was complete the' mixture was heated to a temperature 50Cfand the boiling point of the mixture. The slnrrybbtained was stirred for a quarter of an hour, filtered-,aud washed with V '70 liters of ammonia of the -washing water after being acidifiedwvith' no further precipitation with AgNO 1' Further washing was subsequently carried out with 10 liters of distilled water. After having been-washed'w'ith distilled water, this gel was dried for 6 hours at 180 C. and subsequently calcined for 2 hours at 500 C. in air.

94 g. of the dry aluminum oxide thus obtained was impregnated with ml. of HF solution, containing 0.47 g.

5 of F. The product thus obtained was then dried for 2 hours at C. and calcined in air for 2 hours at 500 C. It was subsequently impregnated with 12.7 g. of ammonium molybdate (81.4% of M00 dissolved in 90 ml. of H 0. "After drying for 2 hours at 180 C. and

70 calcining in air for 2 hours at 500 C.,. the catalyst is prepared for use in the process of the invention by passing hydrogen sulfide gas over it for about 4 hours at 500 C.

A Q, cracked fraction containing 52% by volume protogether with a hydrogcn-containing gas over the above prepared molybdenum sulfide catalyst at a liquid hourly space velocity of 1.5, a temperature of 250 C., and a total pressure of 25 atmospheres. The hydrogen-containing gas is obtained from the catalytic reforming of straight-run naphtha over an acidic platinum catalyst and contains 88 mol percent hydrogen. The hydrogen/ propene ratio is about 7.5 :1. The propene is converted at a high yield to higher boiling branched hydrocarbon with little or no formation of lower boiling hydrocarbons or higher boiling straight-chain hydrocarbons.

We claim as our invention:

1. A process for the conversion of propene into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprises contacting the propene in the presence of hydrogen at a temperature of about 100 C. to about 500 C. and a pressure of about atmospheres to about 100 atmospheres with a catalyst comprising a solid acidic cracking catalyst on which is deposited nickel sulfide, and recovering branched hydrocarbons having 4-6 carbon atoms per molecule.

2. A process for the conversion of propene into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprises contacting propene in the presence of hydrogen at a. temperature of about 100 C. to about 500 C. and a pressure of about 10 atmospheres to about 100 atmospheres with a solid acidic cracking catalyst on which is deposited at sulfide of a metal selected from the group consisting of chromium,

molybdenum, tungsten, iron, cobalt, nickel, and mixtures thereof, and recovering branched hydrocarbons having 4-6 carbon atoms per molecule.

3. A process for the conversion of propene into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprises contacting propene in the presence of hydrogen at a temperature of about 200 C. to about 400 C., a pressure of about 10 atmospheres to about 100 atmospheres, and a liquid-hourly space velocity of from about 0.5 to about 20, with a solid acidic cracking catalyst on which is deposited a sulfide of a metal selected from the group consisting of chromium, molybdenum, tungsten, iron, cobalt, nickel, and mixtures thereof, and recovering branched hydrocarbons having 4-6 carbon atoms per molecule.

4. A process for the conversion of propene into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprism contacting propene in the presence of hydrogen at a temperature of about 100 C. to about 500 C. and a pressure of about 20 atmospheres to about atmospheres, the hydrogen partial pressure being at least 50% of the total pressure, with a catalyst comprising a solid acidic cracking catalyst on which is deposited from about 0.5% to about 15% based on the weight of the final catalyst, of a sulfide of a metal selected from the group consisting of chromium, molybdenum, tungsten, iron, cobalt, nickel and mixtures thereof, and recovering branched hydrocarbons having 4-6 carbon atoms per molecule.

5. A process for the conversion of propcne into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprises contacting propene in the presence of hydrogen at a temperature of about C. to about 500 C. and a pressure of about 10 atmospheres to about 100 atmospheres, the hydrogen partial pressure being at least 50% of the total pressure, with a catalyst comprising a silica-alumina cracking catalyst support having at least 60% by weight silica and on which is deposited from about 0.5% to about 15%, based on the weight of the final catalyst, of a sulfide of a metal selected from the group consisting of chromium, molybdenum, tungsten, iron, cobalt, nickel and mixtures thereof, and recovering branched hydrocarbons having 4-6 carbon atoms per molecule.

6. A process for the conversion of propene into higher boiling branched hydrocarbons having from 4-6 carbon atoms per molecule which comprises contacting propene in the presence of hydrogen at a temperature of about 200 C. to about 400 C., a pressure of about 10 to about 100 atmospheres, the hydrogen partial pressure being at least 50% of the total pressure, and a liquid hourly space velocity of from about 0.5 to about 20 with a catalyst comprising from about 0.5 to about 15%, based on the weight of the final catalyst, nickel sulfide supported on silica-alumina cracking catalyst having at least 60% by weight silica.

References Cited in the file of this patent UNITED STATES PATENTS 1,988,112 Eglolf- Ian. 15, 1937 2,126,001 Fulton et a1. Aug. 9, 1938 2,131,806 Ipaticif et al. Oct. 4, 1938 2,171,207 Boultbee Aug. 29, 1939 2,283,499 Hochmuth May 19, 1942 2,326,585 .Vesterdal Aug. 10, 1943 2,332,276 Stahly Oct. 19, 1943 2,736,689 Stuart Feb. 28, 1956 2,775,638 Milliken et a1. Dec. 25, 1956 

2. A PROCESS FOR THE CONVERSION OF PROPENE INTO HIGHER BOILING BRANCHED HYDROCARBONS HAVING FROM 4-6 CARBON ATOMS PER MOLECULE WHICH COMPRISES CONTACTING PROPENE IN THE PRESENCE OF HYDROGEN AT A TEMPERATURE OF ABOUT 100*C. TO ABOUT 500*C. AND A PRESSURE OF ABOUT 10 ATMOSPHERES TO ABOUT 100 ATMOSPHERESWITH A SOLID ACIDIC CRACKING CATALYST ON WHICH IS DEPOSITED A SULFIDE OF A METAL SELECTED FROM THE GROUP CONSISTING OF CHROMIUM, MOLYBDENUM, TUNGSTEN, IRON, COBALT, NICKEL, AND MIXTURES THEREOF, AND RECOVERING BRANCHED HYDROCARBONS HAVING 4-6 CARBON ATOMS PER MOLECULE. 